• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.349-355
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• 2008

The causes of salt accumulation in soils of plastic film houses nearby Sumjin river estuary in Mokdo-ri($127^{\circ}46'E\;35^{\circ}1'N$), Hadong, Gyeongnam, Korea were investigated in 2006. With chemical properties soils and water analyzed and fertilization status monitored, the study showed that mean salt concentration of soil was much higher at EC $4.3\;dS\;m^{-1}$ than the Korean average (EC $2.9\;dS\;m^{-1}$) in 2000s for plastic film house's soil with exchangeable Na $0.8\;cmol^+\;kg^{-1}$ and water-soluble Cl $232\;mg\;kg^{-1}$, and then might result to salt damage in sensitive crop plants. Salt concentration of ground water used as main irrigation water source contained very high EC with corresponding value of $2.6\;dS\;m^{-1}$. Particularly, increase of EC value was directly proportional with the increased pumping of ground water used as a water-covering system in order to protect the temperature inside plastic film houses from the early winter season. High Na and Cl portion of ions in water might had contributed to the specific ion damage in the crops. Secondly, heavy inputs of chemicals and composts significantly increased the accumulated salts in soil. Conclusively, salt accumulation might had been accelerated by use of salted-groundwater irrigation and heavy fertilization rate. To minimize this problem, ensuring good quality of irrigation water is essential as well as reducing fertilization level.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.557-560
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• 1998

We previously developed and presented the 3D ion implantation simulation code, TRICSI. In this paper, we performed the multiple implants into (100) silicon substrate with our recently enhanced version. Our results for the multiple implants were compared with the previously published SIMS data and obtained the good agreements. In this paper the channeling behaviour of implanted impurity and the damage accumulation are analyzed and discussed in the simple 3D structure, named the Hole structure which has a rectangular implant window.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.227-227
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• 2000

No Abstract, See Full Text

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.169-170
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• 2019

지구단위계획에 의한 택지개발 등의 현장에서 빈번하게 발생하는 토공은 우기 시에 많은 양의 토사침식이 우려된다. 따라서 현장에서 물관리는 매우 중요하며 이를 간과했을때는 대형 재해로 연결 될 수 있으므로 중요하다. 이들 지역은 대부분 소규모지역이므로 수문해석에 필요한 DSM을 드론사진측량으로 손 쉽게 구축할 수 있으며 이를 이용하여 유역면적의 파악, Flow direction, Flow accumulation을 분석한다면 준공까지 효율적으로 물관리가 가능하다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.263-268
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• 2000

The fretting damage of the contact between Zircaloy-4 and Inconel 600 have Investigated. A fretting wear tester was designed to be suitable for this fretting test. In this study, the number of cycles, slip amplitude and normal load were selected as main factors of fretting wear. As the result of this research the wear volume increased with the increase of loads, slip amplitudes and the number of cycles and was more affected by slip amplitudes rather than by load. According to SEM, stick, partial slip, gross slip were observed on the surface of both specimens and wavy worn surfaces as the typical fretting damage were also Investigated due to accumulation of plastic flow.

• Magazine of the Korea Concrete Institute
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• v.10 no.3
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• pp.107-115
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• 1998

반복하중을 받는 무근 및 철근 콘크리트 부재는 하중의 반복작용에 의해 과도한 균열 및 처짐을 유발하고 결과적으로 전체 구조요소의 파괴를 일으킨다. 따라서 하중반복에 의한 누적손상의 진행과정을 정량적으로 평가하여 철근콘크리트 보의 사용성과 안전성을 평가하는 것이 중요하고 특히 취성적 거동 특성을 갖는 전단거동의 경우에 더욱 의미가 있다. 본 연구에서는 반복전단하중에 의한 누적손상의 정량적 분석을 위하여 평균변형도 및 평균응력개념에 기초한 수정압축장이론(modified compression field theory)에 의하여 누적손상 모델을 제안하였다. 본 연구에서 제안된 모델을 통하여 반복전단하중에 의한 처짐과 변형도의 변화를 평가하는데 유용하게 이용될 것으로 사료된다.

• Biomedical Science Letters
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• v.7 no.2
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• pp.79-83
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• 2001

To evaluate an effect of toluene application to skin on the enhancement of liver damage in $CCl_4$-pretreated rats, toluene (35 mg/$cm^2$) was sequentially applied for 5 days to the skin of liver damaged rats with $CCl_4$ (6 times every other day: 0.1 ml/100 g body weight-50% $CCl_4$ in olive oil) On the basis of the functional and morphological findings in rat liver, appling toluene to the skin in liver damaged animals led to the more enhanced liver damage. In addition, by applying toluene to skin of liver damaged rats, the hepatic cytochrome P450 content was somewhat more increased, but the hepatic benzylalcohol dehydrogenase activity was significantly decreased (P<0.001), whereas benzaldehyde dehydrogenase activity was not statistically changed. In conclusion, the toluene application to skin in liver-damaged rat led to enhancement of liver injury that may be due to the accumulation of toluene metabolite in liver.

• Journal of the Korean Society of Safety
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• v.12 no.4
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• pp.86-92
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• 1997

Demand of LPG and LNG will increase continuously due to high calories, clearness, and convenience for usage. These gases are used widely for power plants, industrial plants, and domestic fuel. But accidents related with gas are increasing in proportion to increment of gas usage. Especially LPG has high ignitability due to weak dispersion to air and accumulation at low place because LPG is heavier than air. There are many hazards during transportation as well as production, storage, and usage of LPG. Commonly, tank lorry is used for inland transportation of LPG. If tank lorry were to raise leakage incidents and then LPG released during transporting, the accidents cause serious effects on the environment as well as human damage of surrounding area. In this study, therefore, hazards which cause LPG of tank lorry to leak during transportation were identified and risk of LPG transportation was assessed quantitatively. Also, the result of this study might be a useful measure for predicting damage and preparing safe transportation strategies of LPG tank lorry.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.4
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• pp.189-196
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• 2020

In this study, two full-scale gravity load-designed reinforced concrete corner beam-column joints were tested by being subjected to uniand bi-directional cyclic lateral loading. The test variable was loading type: uni- or bi-directional loading. To investigate the effect of the loading type on the cyclic behavior of joint specimens, damage progression, force-deformation relation, contribution of joint deformation to total drift, joint stress-strain response, and cumulative energy dissipation were investigated. The test data suggest that bidirectional loading can amplify damage accumulation in the joint region.

• Smart Structures and Systems
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• v.2 no.4
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• pp.357-363
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• 2006

Equations describing deformation defects, damage accumulation, and fracture condition have been suggested. Analytical and numerical solutions have been obtained for defects produced by a shear in a fixed direction. Under cyclic loading the number of cycles to failure well fits the empirical Koffin-Manson law. The developed model is expanded to the case of the micro-plastic deformation, which accompanies martensite accommodation in shape memory alloys. Damage of a shape memory specimen has been calculated for two regimes of loading: a constant stress and cyclic variation of temperature across the interval of martensitic transformations, and at a constant temperature corresponding to the pseudoelastic state and cyclic variation of stress. The obtained results are in a good qualitative agreement with available experimental data.